1. Field of the Invention
The present invention relates to a cartridge-type coating machine to which a cartridge for storing paint therein is detachably attached, and relates to the cartridge thereof.
2. Background Art
A rotary atomizing head type coating machine is used widely for coating a target such as a car body.
Recently, coating is desired to be more inexpensive, and to deal with multicoloring for heightening a design quality. Therefore, the coating machine is required to reduce the amount of paint and solvent wasted at the time of changing colors, and to deal with a large number of colors.
To reduce the wasted paint and solvent and to increase colors, there is a conventional rotary atomizing head type coating machine provided with cartridges for storing respective paints of different colors, which are exchangeable to be selectively attached to the coating machine to correspond to a coated target such as a car body.
For example, as described in the Japanese Patent Laid Open Gazette Hei. 11-262699, this rotary atomizing head type coating machine comprises a housing. A front part of the housing is a coating device attachment part to which a coating device is attached. A rear part of the housing is a cartridge attachment part. The coating device includes an air motor having a rotary shaft, and a rotary atomizing head provided on the rotary shaft in front of the air motor.
A feed tube insertion hole, whose front end is opened to the rotary atomizing head and whose rear end is opened to the cartridge attachment part of the housing, is formed axially in the rotary shaft of the air motor constituting the coating device.
In the rotary atomizing head type coating machine, the cartridge is detachably attached to the housing. This cartridge comprises a bomb, in which paint is stored, and a feed tube extended axially outward from the bomb. The bomb is detachably attached into the cartridge attachment part of the housing, and the feed tube is inserted into the feed tube insertion hole.
Cartridges storing respective paints of different colors are prepared, so that one of the cartridges can be selectively attached to the coating machine so as to correspond to a color used for coating.
The cartridge is provided therein with a movable partition. A space in the bomb is divided by the partition into a paint storage chamber, communicated with the feed tube, and an pressure air storage chamber. The cartridge is also provided therein with a cartridge-side pressure air passage for supplying pressure air to the pressure air storage chamber.
Furthermore, the housing is provided therein with a housing-side pressure air passage communicated with the cartridge-side pressure air passage.
By charging pressure air into the pressure air storage chamber through the housing-side and cartridge-side pressure air passages, the movable partition is moved so as to pass paint in the paint storage chamber to the rotary atomizing head through the feed tube.
With regard to the rotary atomizing head type coating machine constructed as the above, a cartridge of a color used for coating is selected from the cartridges of respective colors, and the selected cartridge is attached to the cartridge attachment part of the housing.
Then, by optionally supplying air to the pressure air storage chamber of the cartridge, paint in the paint storage chamber of the cartridge is discharged through the feed tube to the rotary atomizing head. Accordingly, the rotary atomizing head sprays this paint toward a target.
By exchanging the cartridge for a cartridge of another color, coating color can be changed without wasting paint and solvent.
On the other hand, when the cartridge is removed for switching the coating colors after finishing the coating, there is little residual paint in the paint storage chamber. Accordingly, it is necessary to refill the cartridge with paint.
A paint filler for filling the cartridge with paint comprises quick joints extended from paint circulation pipings of respective colors. At the time of filling the paint storage chamber of the cartridge with paint by the paint filler, the cartridge is detached from the housing and returned to a disposition rack. Next, a paint feed opening provided in the cartridge separately from the feed tube is connected to the quick joint so that the cartridge is filled with paint through the quick joint.
However, with regard to the cartridge of the art described in the Japanese Patent Laid Open Gazette Hei. 11-262699, the bomb part, in which paint is stored, and the feed tube part, for guiding the paint in the bomb toward the rotary atomizing head, are formed integrally, and a piston for pressing out the paint from the bomb is disposed in the cartridge, whereby the whole cartridge becomes large and weight thereof increases.
When the empty cartridge is filled with paint, it is necessary to convey not only the paint storage part but the whole cartridge, whereby the handling of the cartridge is complicated and a conveying equipment becomes large.
Furthermore, the cartridges must be provided so as to correspond to the required number of cartridges of each color, and coating lines must be operated so as to correspond to the number of required colors. Accordingly, the number of the cartridges becomes large, and the cartridges, constructed integrally with the paint storage parts and mechanisms for pressing out paint, increase costs.
Moreover, even if any disorder occurs in only the bomb part or only the piston part, the whole cartridge becomes no longer usable.